1. Field of the Invention
The present invention relates to a cable bolt button used on the end of cable mine roof bolts, in particular, a cable bolt button adapted to prevent sliding of the button down the strands of the cable bolt, center the resin cartridge in the bore hole, aid in puncturing the resin cartridge, enhance mixing, and prevent finger gloving.
2. Description of Related Art
Cable mine roof bolts are installed by placing a resin cartridge, including catalyst and adhesive material, into the blind end of a bore hole, inserting the cable bolt into the bore hole so that the upper end of the cable bolt rips open the resin cartridge and the resin flows in the annulus between the bore hole and the cable bolt, rotating the cable bolt to mix the resin catalyst and adhesive and allowing the resin to set about the cable bolt. Typically, the resin may be set after two to three minutes. Once cured, the adhesive helps to anchor the cable segment to the earth and rock.
Cable bolts are the subject of U.S. Pat. Nos. 5,829,922, 5,919,006, 6,074,134, 6,056,482, 6,622,783, 6,527,482, 6,322,290, and 6,270,290, herein incorporated by reference. A button may be placed at the end of the cable bolt to hold the individual strands of the cable together and assist in puncturing the resin cartridge and mixing of the resin when the bolt may be inserted into the bore hole.
Conventional cable bolt buttons have several inadequacies. Conventional buttons are metal sleeves crimped or swaged onto the end of the cable that do not have an end portion covering the distal end of the central strand of the cable bolt. This allows the button to, at times, slide down the strands when the cable bolt is inserted into the bore hole. The conventional buttons have no feature to aid in centering the cartridge with the cable bolt. The conventional buttons are also prone to finger gloving. Finger gloving occurs when the end portion of the punctured resin cartridge becomes attached to the sides of the cable bolt and prevents the resin from directly adhering to the bolt.